Typical responses from owners of existing lenses that are 'threatened' by the new lens. Same kind of resposnes from owners of 24-105 when the 24-70 f/4 was introduced, and the 70-200 f/2.8 owners when the Mark II was introduced.

Without any reviews, these folks were able to determine that the new lens is inferior to what they already own. Impartial conclusions, or divertiture aversion?

Or, maybe these folks are right on this one. The 24-70 f/4 and the 70-200 f/2.8 II were more expensive that what was previously offered. The 70-200 II was an upgraded version, whereas the 24-70 trades focal length for some IQ and macro capabilities, but it still costs more. This one is designed to be slower and to cost less than what is in the market (10-22). The MTF charts don't look radically different, so at the end of the day it may come down to IS and price versus aperture, build quality.

Typical responses from owners of existing lenses that are 'threatened' by the new lens. Same kind of resposnes from owners of 24-105 when the 24-70 f/4 was introduced, and the 70-200 f/2.8 owners when the Mark II was introduced.

Without any reviews, these folks were able to determine that the new lens is inferior to what they already own. Impartial conclusions, or divertiture aversion?

Or, maybe these folks are right on this one. The 24-70 f/4 and the 70-200 f/2.8 II were more expensive that what was previously offered. The 70-200 II was an upgraded version, whereas the 24-70 trades focal length for some IQ and macro capabilities, but it still costs more. This one is designed to be slower and to cost less than what is in the market (10-22). The MTF charts don't look radically different, so at the end of the day it may come down to IS and price versus aperture, build quality.

You see the same kind of reaction from existing 16-35 f/2.8 II owners when the 16-35 f/4 IS was announced on the same day. Now this one is a cheaper and slower lens. How do you explain that? It's a cheaper lens that has IS and a better MTF chart, despite losing out in other areas. Perhaps that lens was to replace the 17-40, but 16-35 f/2.8 II owners feel the need to defend their choice of lens as well.

As for MTF charts, I can easily put it another way, of the 3 crop sensor Canon UWAs, the 10-22 is the WORST performing, beaten by the 11-22 and 10-18 that are both cheaper and IS equipped.

Typical responses from owners of existing lenses that are 'threatened' by the new lens. Same kind of resposnes from owners of 24-105 when the 24-70 f/4 was introduced, and the 70-200 f/2.8 owners when the Mark II was introduced.

Without any reviews, these folks were able to determine that the new lens is inferior to what they already own. Impartial conclusions, or divertiture aversion?

Or, maybe these folks are right on this one. The 24-70 f/4 and the 70-200 f/2.8 II were more expensive that what was previously offered. The 70-200 II was an upgraded version, whereas the 24-70 trades focal length for some IQ and macro capabilities, but it still costs more. This one is designed to be slower and to cost less than what is in the market (10-22). The MTF charts don't look radically different, so at the end of the day it may come down to IS and price versus aperture, build quality.

You see the same kind of reaction from existing 16-35 f/2.8 II owners when the 16-35 f/4 IS was announced on the same day. Now this one is a cheaper and slower lens. How do you explain that? It's a cheaper lens that has IS and a better MTF chart, despite losing out in other areas. Perhaps that lens was to replace the 17-40, but 16-35 f/2.8 II owners feel the need to defend their choice of lens as well.

As for MTF charts, I can easily put it another way, of the 3 crop sensor Canon UWAs, the 10-22 is the WORST performing, beaten by the 11-22 and 10-18 that are both cheaper and IS equipped.

First of all, the plastic mount, slower aperture and slower AF are all pretty big pills to swallow on top of the reduced focal length range - all issues people with 24-105's didn't have to contemplate when looking at the 24-70/4.

And secondly, the MTF charts look pretty damn similar at f8. Comparing the performance at any other aperture is impossible with the data so far - one MTF shows 10mm f3.5 performance and the other 10/4.5. Who's to say what's Canon's simulated MTF of the 10-22 looks like at 10mm when stopped down to 4.5? And at the long end it's even harder to compare due to different aperture and focal length.

This lens is a great addition to the lineup. But it is clearly part of the plastic mount, STM, budget lineup. Not the premium EF-S lens range. The budget range is now looking pretty spectacular, and the premium range is getting a little bit old, but you don't hear of many people preferring the really sharp 18-55 STM over the 17-55. They're just not in the same ball park.

Typical responses from owners of existing lenses that are 'threatened' by the new lens. Same kind of resposnes from owners of 24-105 when the 24-70 f/4 was introduced, and the 70-200 f/2.8 owners when the Mark II was introduced.

Without any reviews, these folks were able to determine that the new lens is inferior to what they already own. Impartial conclusions, or divertiture aversion?

Or, maybe these folks are right on this one. The 24-70 f/4 and the 70-200 f/2.8 II were more expensive that what was previously offered. The 70-200 II was an upgraded version, whereas the 24-70 trades focal length for some IQ and macro capabilities, but it still costs more. This one is designed to be slower and to cost less than what is in the market (10-22). The MTF charts don't look radically different, so at the end of the day it may come down to IS and price versus aperture, build quality.

You see the same kind of reaction from existing 16-35 f/2.8 II owners when the 16-35 f/4 IS was announced on the same day. Now this one is a cheaper and slower lens. How do you explain that? It's a cheaper lens that has IS and a better MTF chart, despite losing out in other areas. Perhaps that lens was to replace the 17-40, but 16-35 f/2.8 II owners feel the need to defend their choice of lens as well.

As for MTF charts, I can easily put it another way, of the 3 crop sensor Canon UWAs, the 10-22 is the WORST performing, beaten by the 11-22 and 10-18 that are both cheaper and IS equipped.

Actually I don't see the 16-35 f/2.8 vs. f/4 IS discussion nearly as contentious as the 24-70 f/4 IS or the 5DII vs. 6D. I don't think 16-35 II users feel the need to defend the 16-35 II versus the 16-35 f/4. For those of us (me included) that have it, if you need f/2.8, then the 16-35 II is your only choice. But I'm considering swapping the f/2.8 for the 16-35 f/4 IS, just like many in this forum. Would I prefer a 16-35 f/2.8 III that is as good if not better than the 16-35 f/4? Yes, but then it's not out yet (if ever), so that is not a choice for now.

And too bad you can't use the 11-22 except on the M, so that is not germane to the discussion. And no, the MTFs are not that different between the 10-22 and the 10-18. Losing 1 stop on APS-C is a much bigger deal than on FF.

I do think the 10-22 and 17-55 will be replaced and those will be much better than the 10-18, but those aren't out yet, and you're comparing new lenses to those nearly 10 years old.

So, I'd thought I'd stop by my local store to see when these would be coming in...and to my surprise, they already had some! Long story short, I walked out with one. I do not have any experience with the 10-22, although I do have the 11-22 for the EOS M (and the 16-35 2.8 for FF).

First impressions...

- The one thing that jumped out at me immediately is how LIGHT this thing is...definitely easy on the arms - balances well on the SL1, too. Great size for traveling.

- Unlike the 16-35 (and 10-22, I believe), but similar to the 11-22, this is NOT an internal zooming lens...the barrel is slightly extended at 10mm, retracts into the body until about 15mm and then extends again SLIGHTLY until 18mm. It barely extends out, though - probably a centimeter at most.

- This has the "STM" focusing mechanism just like all of Canon's newer entry-level lenses...mainly optimized for video. It is virtually silent in a normal environment (in a super-quiet room, you CAN hear a faint, high-pitched whine as the lens focuses).

- The filter size is 67mm, and the front thread (?) does not rotate when focusing.

- For those that have the M + adapter: there is a noticeable difference in FOV between 11mm and 10mm (this lens can go wider), and this lens is light enough so this could be another UWA option to consider._______________

So, overall thoughts...

Positives

- Light, compact, easy for travel

- Very good center sharpness throughout the range

- IS works well (I was able to get keepers down to 1/4...for those using it with a 70D or larger camera you can likely do better)

- Very affordable at $300, and very high price/performance ratio

Negatives

- Some edge/corner softness observed, particularly at 10mm

- Purple fringing showed up in a few of my shots (wide end)

__________________

So...I think that this is a great lens for the money, although those looking for top UWA performance will want to look elsewhere (and likely will, anyway). Compared to the 11-22, I found the 10-18 to be softer near the corners...but that's more of a testament to how outstanding the 11-22 is, more so than a condemnation of the 10-18. Compared to the 16-35 on FF, the difference between center and corner sharpness seems less drastic on the 10-18. Unfortunately I cannot compare it to the 10-22, so I'll leave that one to someone else...

In the end, I wasn't blown away...then again, I didn't necessarily expect to be. But it is what it is - an entry-level/travel-sized UWA lens, and for $300, I'm not going to complain too much. It is plenty good enough for vacation snapshots and casual shooting. I can be pretty demanding when it comes to IQ, anyway.